Mechanosensitive ion channel Piezo1 promotes prostate cancer development through the activation of the Akt/mTOR pathway and acceleration of cell cycle

Glycolysis is suppressed by DCZ0801-induced inactivation of the Akt/mTOR pathway in Multiple Myeloma

Multiple myeloma (MM) is a highly invasive and incurable plasma cell malignant disease with frequent recurrence. DCZ0801 is a natural compound synthesized from osalmide and pterostilbene and has few adverse effects. Here, we aimed to observe the therapeutic effects of DCZ0801 on myeloma cells and clarify the specific molecular mechanism underlying its anti-tumor activity. The Cell Counting Kit-8 assay, apoptosis detection, cell cycle analysis, western blot analysis, and tumor xenograft models were used to determine the effect of DCZ0801 treatment both in vivo and in vitro. We revealed that DCZ0801 treatment suppressed MM cell survival by inducing apoptosis and blocking the cell cycle at S phase. Deranged glycolysis and downregulated Akt/mTOR pathway may also be responsible for cell proliferation inhibition. Moreover, DCZ0801 treatment could remarkably reduce the tumor size in the xenograft mouse model. Therefore these findings indicate that DCZ0801 can be used as a novel therapeutic drug for patients suffering from multiple myeloma.

The Mechanical Microenvironment in Breast Cancer

Mechanotransduction is the interpretation of physical cues by cells through mechanosensation mechanisms that elegantly translate mechanical stimuli into biochemical signaling pathways. While mechanical stress and their resulting cellular responses occur in normal physiologic contexts, there are a variety of cancer-associated physical cues present in the tumor microenvironment that are pathological in breast cancer. Mechanistic in vitro data and in vivo evidence currently support three mechanical stressors as mechanical modifiers in breast cancer that will be the focus of this review: stiffness, interstitial fluid pressure, and solid stress. Increases in stiffness, interstitial fluid pressure, and solid stress are thought to promote malignant phenotypes in normal breast epithelial cells, as well as exacerbate malignant phenotypes in breast cancer cells.

Upregulation of Piezo1 Is a Novel Prognostic Indicator in Glioma Patients

Purpose

Previous study reported that Piezo1 was highly expressed in glioma and promoted the proliferation of glioma cells, suggesting that Piezo1 overexpression might contribute to the poor prognosis of patients. Thus, this study aimed to identify whether Piezo1 may become a new prognostic biomarker for glioma patients.

Patients and Methods

Firstly, Piezo1 expression of gliomas was analyzed through GEO and Oncomine dataset, and verified by qRT-PCR and immunohistochemistry (IHC) methods. A total of 183 glioma patients were included in this study between January 2010 and December 2014. Kaplan-Meier survival analyses, Cox regression analyses and ROC curve analyses were performed to assess the diagnostic and prognostic values of Piezo1 in glioma patients.

Results

In this study, Piezo1 was identified to be highly expressed in gliomas, and increased with WHO grade. Chi-square test results showed that Piezo1 expression was significantly related to age (P=0.00), WHO grade (P=0.00), Histopathology (P=0.00), IDH1 mutation (P=0.00) and chemotherapy (P=0.00). Kaplan-Meier analysis showed that the overall survival (OS) of patients with high Piezo1 expression was significantly worse than that of patients with low Piezo1 expression (HR=3.39, 95% CI=2.40-4.81, P<0.0001). A multivariate Cox regression analysis revealed that Piezo1 might be an independent prognostic factor for glioma patients (HR=1.34, 95% CI=1.23-1.47, P=0.000). The area under the ROC curve (AUC) of 1-, 3-, and 5-year overall survival for Piezo1 overexpression was 0.820 (P=0.000), 0.849 (P=0.000), and 0.861 (P=0.000), respectively.

Conclusion

Piezo1 was overexpressed in glioma samples. Piezo1 overexpression as an independent prognostic factor adversely affects the prognosis of patients, which could be a new novel prognostic indicator in glioma patients.

Role of Calcium Signaling in Prostate Cancer Progression: Effects on Cancer Hallmarks and Bone Metastatic Mechanisms

Advanced prostate cancers that progress to tumor metastases are often considered incurable or difficult to treat. The etiology of prostate cancers is multi-factorial. Among other factors, de-regulation of calcium signals in prostate tumor cells mediates several pathological dysfunctions associated with tumor progression. Calcium plays a relevant role on tumor cell death, proliferation, motility-invasion and tumor metastasis. Calcium controls molecular factors and signaling pathways involved in the development of prostate cancer and its progression. Such factors and pathways include calcium channels and calcium-binding proteins. Nevertheless, the involvement of calcium signaling on prostate cancer predisposition for bone tropism has been relatively unexplored. In this regard, a diversity of mechanisms triggers transient accumulation of intracellular calcium in prostate cancer cells, potentially favoring bone metastases development. New therapies for the treatment of prostate cancer include compounds characterized by potent and specific actions that target calcium channels/transporters or pumps. These novel drugs for prostate cancer treatment encompass calcium-ATPase inhibitors, voltage-gated calcium channel inhibitors, transient receptor potential (TRP) channel regulators or Orai inhibitors. This review details the latest results that have evaluated the relationship between calcium signaling and progression of prostate cancer, as well as potential therapies aiming to modulate calcium signaling in prostate tumor progression.